Aquarium



FIG. 1 is a front perspective view of an aquarium, showing our new design;

FIG. 2 is a rear perspective view thereof;

FIG. 3 is a left side elevational view thereof, the right side being a mirror image of the left side shown; and

FIG. 4 is another front perspective view thereof with the cover removed for convenience of illustration. 

The ornamental design for an aquarium, substantially as shown and described. 